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/* USRP E310 Firmware Atmel AVR SPI driver
* Copyright (C) 2014 Ettus Research
* This file is part of the USRP E310 Firmware
* The USRP E310 Firmware is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
* The USRP E310 Firmware is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License
* along with the USRP E310 Firmware. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* \file spi.h
* \brief Atmel AVR SPI driver
*/
#ifndef SPI_H
#define SPI_H
#include <stdlib.h>
typedef enum spi_type {
SPI_TYPE_MASTER = 0x00,
SPI_TYPE_SLAVE = 0x01
} spi_type_t;
typedef enum spi_mode {
SPI_MODE_0 = 0x00, /** CPOL=0, CPHA=0 */
SPI_MODE_1 = 0x01, /** CPOL=0, CPHA=1 */
SPI_MODE_2 = 0x02, /** CPOL=1, CPHA=0 */
SPI_MODE_3 = 0x03, /** CPOL=1, CPHA=1 */
} spi_mode_t;
/* note that this assumes a clock speed of 8MHz */
typedef enum spi_speed {
SPI_SPEED_2M = 0x00,
SPI_SPEED_500K = 0x01,
SPI_SPEED_125K = 0x02,
SPI_SPEED_62_5K = 0x03,
} spi_speed_t;
typedef enum spi_order {
SPI_MSB_FIRST = 0x00,
SPI_LSB_FIRST = 0x01,
} spi_order_t;
/**
* \brief Initialize the AVR's SPI module
* \param[in] master Operate as master
* \param[in] order Whether to send the LSB first
* \param[in] mode Which clock / phase configuration to use
* \param[in] speed Which speed to use
*/
void spi_init(spi_type_t type, spi_order_t order, spi_mode_t mode, spi_speed_t speed);
/**
* \brief Transact one byte to the slave and receive one byte
* \param[in] mode Whether we're using the SPI in MSB or LSB first mode
* \param[in] speed Which speed to use, note that these speeds are based on a prescaler,
and the values are correct for a FCLK of 8 MHz
*/
uint8_t spi_transact(uint8_t data);
void spi_transact_buf(uint8_t *in, uint8_t *out, uint8_t size);
/**
* \brief Wait till transaction is done
*/
void spi_wait_till_done(void);
#endif /* SPI_H */
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